Thanks so much for all the replies fellas, really appreciate it.

hmm! the rad could be an NC30 one then, the peg is definitely rounded but it doesn't fit all the way on it, id say its probably about 10-15mm off, and indeed you'd struggle to get a piece of paper between the bottom and the cam cover. Will snap some pics later.

If you could have a look whenever gavins that'd be awesome! no rush :)

Cheers.

Here's a (crummy) pic of my stock NC35 clipon. You can see it's secured by a single pinch bolt, has a ridge in the centre and the bars are risen up almost to the level of the top yoke. You can see the tab on the left edge that locates into the top yoke.